RP-HPLC法同时测定半夏药材中4种有机酸的含量

目的: 采用RP-HPLC法同时测定半夏药材中草酸(oxalic acid,OA)、柠檬酸(citric acid,CA)、苹果酸(malic acid,MA)、琥珀酸(succinic acid,SA)的含量。方法: 采用Gemini-C₁₈(4.6 mm×250 mm,5 μm)色谱柱,以0.03 mol·L^-1磷酸二氢铵缓冲液(以磷酸调节pH=2.0)-甲醇(97:3)为流动相,流速0.8 mL·min^-1,柱温30 ℃,检测波长210 nm。结果: 草酸、柠檬酸、苹果酸和琥珀酸的线性方程分别为Y=1.194×10⁴X+1.938×10³(r=0.999 5),Y=291X+263(r=0.999 6),Y=7.446×10³X+260(r=0.999 9),Y=2.332×10³X-1.727×10³(r=0.999 6),它们的质量浓度分别在2.28~36.48、12.32~197.1、2.62~41.86、12.56~201.0 μg·mL^-1范围内线性关系良好,低、中、高浓度平均加样回收率(n=9)在96.9%与98.0%之间。10个不同产地半夏4种有机酸的总含量在0.295%-2.086%之间。结论: 10个不同产地半夏4种有机酸总含量以四川西昌最高,四川遂宁最低,该方法经方法学验证,可为半夏药材的质量控制提供参考。

Objective: To establish a RP-HPLC method for simultaneous determination of oxalic acid,citric acid,malic acid and succinic acid in Pinelliae Rhizoma. Methods: The separation was performed on a Gemini-C₁₈ analytical column (4.6 mm×250 mm,5 μm)with 0.03 mol·L^-1 ammonium dihydrogen phosphate buffer solution (adjusted pH to 2.0 with phosphoric acid)-methanol (97:3)as the mobile phase at a flow rate of 0.8 mL·min^-1.The detection wavelength was 210 nm and the column temperature was 30 ℃. Results: The regression equations of oxalic acid,citric acid,malic acid and succinic acid were as follows:Y=1.194×10⁴X+1.938×10³ (r=0.999 5),Y=291X+263 (r=0.999 6),Y=7.446×10³X+260 (r=0.999 9),Y=2.332×10³X-1.727×10³ (r=0.999 6).Linear ranges of oxalic acid,citric acid,malic acid and succinic acid were 2.28-36.48 μg·mL^-1,12.32-197.1 μg·mL^-1,2.62-41.86 μg·mL^-1,12.56-201.0 μg·mL^-1,respectively.Their average recoveries (n=9)at low,medium and high concentrations fell between 96.9% and 98.0%,the total content of the four organic acids from 10 different origins ranged from 0.295% to 2.086%. Conclusion: The total content of the four organic acids in samples from Xichang district,Sichuan province was the highest and that from Suining district,Sichuan province was the lowest.By the methodology validation,the RP-HPLC method was proved to be applicable as a standard for the quality control of Pinelliae Rhizoma.